An issue was discovered in the Linux kernel through 5.19.8. drivers/firmware/efi/capsule-loader.c has a race condition with a resultant use-after-free.

In the Linux kernel, the following vulnerability has been resolved: ice: Fix race condition during interface enslave Commit 5dbbbd01cbba83 ("ice: Avoid RTNL lock when re-creating auxiliary device") changes a process of re-creation of aux device so ice_plug_aux_dev() is called from ice_service_task() context. This unfortunately opens a race window that can result in dead-lock when interface has left LAG and immediately enters LAG again. Reproducer: ``` #!/bin/sh ip link add lag0 type bond mode 1 miimon 100 ip link set lag0 for n in {1..10}; do echo Cycle: $n ip link set ens7f0 master lag0 sleep 1 ip link set ens7f0 nomaster done ``` This results in: [20976.208697] Workqueue: ice ice_service_task [ice] [20976.213422] Call Trace: [20976.215871] __schedule+0x2d1/0x830 [20976.219364] schedule+0x35/0xa0 [20976.222510] schedule_preempt_disabled+0xa/0x10 [20976.227043] __mutex_lock.isra.7+0x310/0x420 [20976.235071] enum_all_gids_of_dev_cb+0x1c/0x100 [ib_core] [20976.251215] ib_enum_roce_netdev+0xa4/0xe0 [ib_core] [20976.256192] ib_cache_setup_one+0x33/0xa0 [ib_core] [20976.261079] ib_register_device+0x40d/0x580 [ib_core] [20976.266139] irdma_ib_register_device+0x129/0x250 [irdma] [20976.281409] irdma_probe+0x2c1/0x360 [irdma] [20976.285691] auxiliary_bus_probe+0x45/0x70 [20976.289790] really_probe+0x1f2/0x480 [20976.298509] driver_probe_device+0x49/0xc0 [20976.302609] bus_for_each_drv+0x79/0xc0 [20976.306448] __device_attach+0xdc/0x160 [20976.310286] bus_probe_device+0x9d/0xb0 [20976.314128] device_add+0x43c/0x890 [20976.321287] __auxiliary_device_add+0x43/0x60 [20976.325644] ice_plug_aux_dev+0xb2/0x100 [ice] [20976.330109] ice_service_task+0xd0c/0xed0 [ice] [20976.342591] process_one_work+0x1a7/0x360 [20976.350536] worker_thread+0x30/0x390 [20976.358128] kthread+0x10a/0x120 [20976.365547] ret_from_fork+0x1f/0x40 ... [20976.438030] task:ip state:D stack: 0 pid:213658 ppid:213627 flags:0x00004084 [20976.446469] Call Trace: [20976.448921] __schedule+0x2d1/0x830 [20976.452414] schedule+0x35/0xa0 [20976.455559] schedule_preempt_disabled+0xa/0x10 [20976.460090] __mutex_lock.isra.7+0x310/0x420 [20976.464364] device_del+0x36/0x3c0 [20976.467772] ice_unplug_aux_dev+0x1a/0x40 [ice] [20976.472313] ice_lag_event_handler+0x2a2/0x520 [ice] [20976.477288] notifier_call_chain+0x47/0x70 [20976.481386] __netdev_upper_dev_link+0x18b/0x280 [20976.489845] bond_enslave+0xe05/0x1790 [bonding] [20976.494475] do_setlink+0x336/0xf50 [20976.502517] __rtnl_newlink+0x529/0x8b0 [20976.543441] rtnl_newlink+0x43/0x60 [20976.546934] rtnetlink_rcv_msg+0x2b1/0x360 [20976.559238] netlink_rcv_skb+0x4c/0x120 [20976.563079] netlink_unicast+0x196/0x230 [20976.567005] netlink_sendmsg+0x204/0x3d0 [20976.570930] sock_sendmsg+0x4c/0x50 [20976.574423] ____sys_sendmsg+0x1eb/0x250 [20976.586807] ___sys_sendmsg+0x7c/0xc0 [20976.606353] __sys_sendmsg+0x57/0xa0 [20976.609930] do_syscall_64+0x5b/0x1a0 [20976.613598] entry_SYSCALL_64_after_hwframe+0x65/0xca 1. Command 'ip link ... set nomaster' causes that ice_plug_aux_dev() is called from ice_service_task() context, aux device is created and associated device->lock is taken. 2. Command 'ip link ... set master...' calls ice's notifier under RTNL lock and that notifier calls ice_unplug_aux_dev(). That function tries to take aux device->lock but this is already taken by ice_plug_aux_dev() in step 1 3. Later ice_plug_aux_dev() tries to take RTNL lock but this is already taken in step 2 4. Dead-lock The patch fixes this issue by following changes: - Bit ICE_FLAG_PLUG_AUX_DEV is kept to be set during ice_plug_aux_dev() call in ice_service_task() - The bit is checked in ice_clear_rdma_cap() and only if it is not set then ice_unplug_aux_dev() is called. If it is set (in other words plugging of aux device was requested and ice_plug_aux_dev() is potentially running) then the function only clears the ---truncated---

In the Linux kernel, the following vulnerability has been resolved: vfs: fix race between evice_inodes() and find_inode()&iput() Hi, all Recently I noticed a bug[1] in btrfs, after digged it into and I believe it'a race in vfs. Let's assume there's a inode (ie ino 261) with i_count 1 is called by iput(), and there's a concurrent thread calling generic_shutdown_super(). cpu0: cpu1: iput() // i_count is 1 ->spin_lock(inode) ->dec i_count to 0 ->iput_final() generic_shutdown_super() ->__inode_add_lru() ->evict_inodes() // cause some reason[2] ->if (atomic_read(inode->i_count)) continue; // return before // inode 261 passed the above check // list_lru_add_obj() // and then schedule out ->spin_unlock() // note here: the inode 261 // was still at sb list and hash list, // and I_FREEING|I_WILL_FREE was not been set btrfs_iget() // after some function calls ->find_inode() // found the above inode 261 ->spin_lock(inode) // check I_FREEING|I_WILL_FREE // and passed ->__iget() ->spin_unlock(inode) // schedule back ->spin_lock(inode) // check (I_NEW|I_FREEING|I_WILL_FREE) flags, // passed and set I_FREEING iput() ->spin_unlock(inode) ->spin_lock(inode) ->evict() // dec i_count to 0 ->iput_final() ->spin_unlock() ->evict() Now, we have two threads simultaneously evicting the same inode, which may trigger the BUG(inode->i_state & I_CLEAR) statement both within clear_inode() and iput(). To fix the bug, recheck the inode->i_count after holding i_lock. Because in the most scenarios, the first check is valid, and the overhead of spin_lock() can be reduced. If there is any misunderstanding, please let me know, thanks. [1]: https://lore.kernel.org/linux-btrfs/000000000000eabe1d0619c48986@google.com/ [2]: The reason might be 1. SB_ACTIVE was removed or 2. mapping_shrinkable() return false when I reproduced the bug.

In the Linux kernel, the following vulnerability has been resolved: net/smc: Transitional solution for clcsock race issue We encountered a crash in smc_setsockopt() and it is caused by accessing smc->clcsock after clcsock was released. BUG: kernel NULL pointer dereference, address: 0000000000000020 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP PTI CPU: 1 PID: 50309 Comm: nginx Kdump: loaded Tainted: G E 5.16.0-rc4+ #53 RIP: 0010:smc_setsockopt+0x59/0x280 [smc] Call Trace: <TASK> __sys_setsockopt+0xfc/0x190 __x64_sys_setsockopt+0x20/0x30 do_syscall_64+0x34/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f16ba83918e </TASK> This patch tries to fix it by holding clcsock_release_lock and checking whether clcsock has already been released before access. In case that a crash of the same reason happens in smc_getsockopt() or smc_switch_to_fallback(), this patch also checkes smc->clcsock in them too. And the caller of smc_switch_to_fallback() will identify whether fallback succeeds according to the return value.

In the Linux kernel, the following vulnerability has been resolved: sched/fair: Fix fault in reweight_entity Syzbot found a GPF in reweight_entity. This has been bisected to commit 4ef0c5c6b5ba ("kernel/sched: Fix sched_fork() access an invalid sched_task_group") There is a race between sched_post_fork() and setpriority(PRIO_PGRP) within a thread group that causes a null-ptr-deref in reweight_entity() in CFS. The scenario is that the main process spawns number of new threads, which then call setpriority(PRIO_PGRP, 0, -20), wait, and exit. For each of the new threads the copy_process() gets invoked, which adds the new task_struct and calls sched_post_fork() for it. In the above scenario there is a possibility that setpriority(PRIO_PGRP) and set_one_prio() will be called for a thread in the group that is just being created by copy_process(), and for which the sched_post_fork() has not been executed yet. This will trigger a null pointer dereference in reweight_entity(), as it will try to access the run queue pointer, which hasn't been set. Before the mentioned change the cfs_rq pointer for the task has been set in sched_fork(), which is called much earlier in copy_process(), before the new task is added to the thread_group. Now it is done in the sched_post_fork(), which is called after that. To fix the issue the remove the update_load param from the update_load param() function and call reweight_task() only if the task flag doesn't have the TASK_NEW flag set.

A race condition was discovered in get_old_root in fs/btrfs/ctree.c in the Linux kernel through 5.11.8. It allows attackers to cause a denial of service (BUG) because of a lack of locking on an extent buffer before a cloning operation, aka CID-dbcc7d57bffc.

In the Linux kernel, the following vulnerability has been resolved: platform/x86: lenovo-yoga-tab2-pro-1380-fastcharger: fix serdev race The yt2_1380_fc_serdev_probe() function calls devm_serdev_device_open() before setting the client ops via serdev_device_set_client_ops(). This ordering can trigger a NULL pointer dereference in the serdev controller's receive_buf handler, as it assumes serdev->ops is valid when SERPORT_ACTIVE is set. This is similar to the issue fixed in commit 5e700b384ec1 ("platform/chrome: cros_ec_uart: properly fix race condition") where devm_serdev_device_open() was called before fully initializing the device. Fix the race by ensuring client ops are set before enabling the port via devm_serdev_device_open(). Note, serdev_device_set_baudrate() and serdev_device_set_flow_control() calls should be after the devm_serdev_device_open() call.

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix type confusion via race condition when using ipc_msg_send_request req->handle is allocated using ksmbd_acquire_id(&ipc_ida), based on ida_alloc. req->handle from ksmbd_ipc_login_request and FSCTL_PIPE_TRANSCEIVE ioctl can be same and it could lead to type confusion between messages, resulting in access to unexpected parts of memory after an incorrect delivery. ksmbd check type of ipc response but missing add continue to check next ipc reponse.

An issue was discovered in the Linux kernel before 5.11.7. usbip_sockfd_store in drivers/usb/usbip/stub_dev.c allows attackers to cause a denial of service (GPF) because the stub-up sequence has race conditions during an update of the local and shared status, aka CID-9380afd6df70.

In the Linux kernel, the following vulnerability has been resolved: firmware: qcom: uefisecapp: fix efivars registration race Since the conversion to using the TZ allocator, the efivars service is registered before the memory pool has been allocated, something which can lead to a NULL-pointer dereference in case of a racing EFI variable access. Make sure that all resources have been set up before registering the efivars.

In the Linux kernel, the following vulnerability has been resolved: platform/chrome: cros_ec_uart: properly fix race condition The cros_ec_uart_probe() function calls devm_serdev_device_open() before it calls serdev_device_set_client_ops(). This can trigger a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000000 ... Call Trace: <TASK> ... ? ttyport_receive_buf A simplified version of crashing code is as follows: static inline size_t serdev_controller_receive_buf(struct serdev_controller *ctrl, const u8 *data, size_t count) { struct serdev_device *serdev = ctrl->serdev; if (!serdev || !serdev->ops->receive_buf) // CRASH! return 0; return serdev->ops->receive_buf(serdev, data, count); } It assumes that if SERPORT_ACTIVE is set and serdev exists, serdev->ops will also exist. This conflicts with the existing cros_ec_uart_probe() logic, as it first calls devm_serdev_device_open() (which sets SERPORT_ACTIVE), and only later sets serdev->ops via serdev_device_set_client_ops(). Commit 01f95d42b8f4 ("platform/chrome: cros_ec_uart: fix race condition") attempted to fix a similar race condition, but while doing so, made the window of error for this race condition to happen much wider. Attempt to fix the race condition again, making sure we fully setup before calling devm_serdev_device_open().

An issue was discovered in include/asm-generic/tlb.h in the Linux kernel before 5.19. Because of a race condition (unmap_mapping_range versus munmap), a device driver can free a page while it still has stale TLB entries. This only occurs in situations with VM_PFNMAP VMAs.

In the Linux kernel, the following vulnerability has been resolved: PCI: of_property: Return error for int_map allocation failure Return -ENOMEM from of_pci_prop_intr_map() if kcalloc() fails to prevent a NULL pointer dereference in this case. [bhelgaas: commit log]

In the Linux kernel, the following vulnerability has been resolved: nvme: tcp: avoid race between queue_lock lock and destroy Commit 76d54bf20cdc ("nvme-tcp: don't access released socket during error recovery") added a mutex_lock() call for the queue->queue_lock in nvme_tcp_get_address(). However, the mutex_lock() races with mutex_destroy() in nvme_tcp_free_queue(), and causes the WARN below. DEBUG_LOCKS_WARN_ON(lock->magic != lock) WARNING: CPU: 3 PID: 34077 at kernel/locking/mutex.c:587 __mutex_lock+0xcf0/0x1220 Modules linked in: nvmet_tcp nvmet nvme_tcp nvme_fabrics iw_cm ib_cm ib_core pktcdvd nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables qrtr sunrpc ppdev 9pnet_virtio 9pnet pcspkr netfs parport_pc parport e1000 i2c_piix4 i2c_smbus loop fuse nfnetlink zram bochs drm_vram_helper drm_ttm_helper ttm drm_kms_helper xfs drm sym53c8xx floppy nvme scsi_transport_spi nvme_core nvme_auth serio_raw ata_generic pata_acpi dm_multipath qemu_fw_cfg [last unloaded: ib_uverbs] CPU: 3 UID: 0 PID: 34077 Comm: udisksd Not tainted 6.11.0-rc7 #319 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:__mutex_lock+0xcf0/0x1220 Code: 08 84 d2 0f 85 c8 04 00 00 8b 15 ef b6 c8 01 85 d2 0f 85 78 f4 ff ff 48 c7 c6 20 93 ee af 48 c7 c7 60 91 ee af e8 f0 a7 6d fd <0f> 0b e9 5e f4 ff ff 48 b8 00 00 00 00 00 fc ff df 4c 89 f2 48 c1 RSP: 0018:ffff88811305f760 EFLAGS: 00010286 RAX: 0000000000000000 RBX: ffff88812c652058 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffff88811305f8b0 R08: 0000000000000001 R09: ffffed1075c36341 R10: ffff8883ae1b1a0b R11: 0000000000010498 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: ffff88812c652058 FS: 00007f9713ae4980(0000) GS:ffff8883ae180000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fcd78483c7c CR3: 0000000122c38000 CR4: 00000000000006f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? __warn.cold+0x5b/0x1af ? __mutex_lock+0xcf0/0x1220 ? report_bug+0x1ec/0x390 ? handle_bug+0x3c/0x80 ? exc_invalid_op+0x13/0x40 ? asm_exc_invalid_op+0x16/0x20 ? __mutex_lock+0xcf0/0x1220 ? nvme_tcp_get_address+0xc2/0x1e0 [nvme_tcp] ? __pfx___mutex_lock+0x10/0x10 ? __lock_acquire+0xd6a/0x59e0 ? nvme_tcp_get_address+0xc2/0x1e0 [nvme_tcp] nvme_tcp_get_address+0xc2/0x1e0 [nvme_tcp] ? __pfx_nvme_tcp_get_address+0x10/0x10 [nvme_tcp] nvme_sysfs_show_address+0x81/0xc0 [nvme_core] dev_attr_show+0x42/0x80 ? __asan_memset+0x1f/0x40 sysfs_kf_seq_show+0x1f0/0x370 seq_read_iter+0x2cb/0x1130 ? rw_verify_area+0x3b1/0x590 ? __mutex_lock+0x433/0x1220 vfs_read+0x6a6/0xa20 ? lockdep_hardirqs_on+0x78/0x100 ? __pfx_vfs_read+0x10/0x10 ksys_read+0xf7/0x1d0 ? __pfx_ksys_read+0x10/0x10 ? __x64_sys_openat+0x105/0x1d0 do_syscall_64+0x93/0x180 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? __pfx_ksys_read+0x10/0x10 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on_prepare+0x16d/0x400 ? do_syscall_64+0x9f/0x180 ? lockdep_hardirqs_on+0x78/0x100 ? do_syscall_64+0x9f/0x180 ? do_syscall_64+0x9f/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f9713f55cfa Code: 55 48 89 e5 48 83 ec 20 48 89 55 e8 48 89 75 f0 89 7d f8 e8 e8 74 f8 ff 48 8b 55 e8 48 8b 75 f0 4 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: ipv4: Fix uninit-value access in __ip_make_skb() KMSAN reported uninit-value access in __ip_make_skb() [1]. __ip_make_skb() tests HDRINCL to know if the skb has icmphdr. However, HDRINCL can cause a race condition. If calling setsockopt(2) with IP_HDRINCL changes HDRINCL while __ip_make_skb() is running, the function will access icmphdr in the skb even if it is not included. This causes the issue reported by KMSAN. Check FLOWI_FLAG_KNOWN_NH on fl4->flowi4_flags instead of testing HDRINCL on the socket. Also, fl4->fl4_icmp_type and fl4->fl4_icmp_code are not initialized. These are union in struct flowi4 and are implicitly initialized by flowi4_init_output(), but we should not rely on specific union layout. Initialize these explicitly in raw_sendmsg(). [1] BUG: KMSAN: uninit-value in __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 ip_finish_skb include/net/ip.h:243 [inline] ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508 raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x274/0x3c0 net/socket.c:745 __sys_sendto+0x62c/0x7b0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Uninit was created at: slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577 __alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1318 [inline] __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128 ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365 raw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x274/0x3c0 net/socket.c:745 __sys_sendto+0x62c/0x7b0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 CPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014

In the Linux kernel, the following vulnerability has been resolved: fgraph: Add READ_ONCE() when accessing fgraph_array[] In __ftrace_return_to_handler(), a loop iterates over the fgraph_array[] elements, which are fgraph_ops. The loop checks if an element is a fgraph_stub to prevent using a fgraph_stub afterward. However, if the compiler reloads fgraph_array[] after this check, it might race with an update to fgraph_array[] that introduces a fgraph_stub. This could result in the stub being processed, but the stub contains a null "func_hash" field, leading to a NULL pointer dereference. To ensure that the gops compared against the fgraph_stub matches the gops processed later, add a READ_ONCE(). A similar patch appears in commit 63a8dfb ("function_graph: Add READ_ONCE() when accessing fgraph_array[]").

In the Linux kernel, the following vulnerability has been resolved: accel/ivpu: Prevent recovery invocation during probe and resume Refactor IPC send and receive functions to allow correct handling of operations that should not trigger a recovery process. Expose ivpu_send_receive_internal(), which is now utilized by the D0i3 entry, DCT initialization, and HWS initialization functions. These functions have been modified to return error codes gracefully, rather than initiating recovery. The updated functions are invoked within ivpu_probe() and ivpu_resume(), ensuring that any errors encountered during these stages result in a proper teardown or shutdown sequence. The previous approach of triggering recovery within these functions could lead to a race condition, potentially causing undefined behavior and kernel crashes due to null pointer dereferences.

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu: Defer probe of clients after smmu device bound Null pointer dereference occurs due to a race between smmu driver probe and client driver probe, when of_dma_configure() for client is called after the iommu_device_register() for smmu driver probe has executed but before the driver_bound() for smmu driver has been called. Following is how the race occurs: T1:Smmu device probe T2: Client device probe really_probe() arm_smmu_device_probe() iommu_device_register() really_probe() platform_dma_configure() of_dma_configure() of_dma_configure_id() of_iommu_configure() iommu_probe_device() iommu_init_device() arm_smmu_probe_device() arm_smmu_get_by_fwnode() driver_find_device_by_fwnode() driver_find_device() next_device() klist_next() /* null ptr assigned to smmu */ /* null ptr dereference while smmu->streamid_mask */ driver_bound() klist_add_tail() When this null smmu pointer is dereferenced later in arm_smmu_probe_device, the device crashes. Fix this by deferring the probe of the client device until the smmu device has bound to the arm smmu driver. [will: Add comment]

In the Linux kernel, the following vulnerability has been resolved: i40e: fix race condition by adding filter's intermediate sync state Fix a race condition in the i40e driver that leads to MAC/VLAN filters becoming corrupted and leaking. Address the issue that occurs under heavy load when multiple threads are concurrently modifying MAC/VLAN filters by setting mac and port VLAN. 1. Thread T0 allocates a filter in i40e_add_filter() within i40e_ndo_set_vf_port_vlan(). 2. Thread T1 concurrently frees the filter in __i40e_del_filter() within i40e_ndo_set_vf_mac(). 3. Subsequently, i40e_service_task() calls i40e_sync_vsi_filters(), which refers to the already freed filter memory, causing corruption. Reproduction steps: 1. Spawn multiple VFs. 2. Apply a concurrent heavy load by running parallel operations to change MAC addresses on the VFs and change port VLANs on the host. 3. Observe errors in dmesg: "Error I40E_AQ_RC_ENOSPC adding RX filters on VF XX, please set promiscuous on manually for VF XX". Exact code for stable reproduction Intel can't open-source now. The fix involves implementing a new intermediate filter state, I40E_FILTER_NEW_SYNC, for the time when a filter is on a tmp_add_list. These filters cannot be deleted from the hash list directly but must be removed using the full process.

In the Linux kernel, the following vulnerability has been resolved: drm/panthor: Fix race when converting group handle to group object XArray provides it's own internal lock which protects the internal array when entries are being simultaneously added and removed. However there is still a race between retrieving the pointer from the XArray and incrementing the reference count. To avoid this race simply hold the internal XArray lock when incrementing the reference count, this ensures there cannot be a racing call to xa_erase().

In the Linux kernel, the following vulnerability has been resolved: fsnotify: clear PARENT_WATCHED flags lazily In some setups directories can have many (usually negative) dentries. Hence __fsnotify_update_child_dentry_flags() function can take a significant amount of time. Since the bulk of this function happens under inode->i_lock this causes a significant contention on the lock when we remove the watch from the directory as the __fsnotify_update_child_dentry_flags() call from fsnotify_recalc_mask() races with __fsnotify_update_child_dentry_flags() calls from __fsnotify_parent() happening on children. This can lead upto softlockup reports reported by users. Fix the problem by calling fsnotify_update_children_dentry_flags() to set PARENT_WATCHED flags only when parent starts watching children. When parent stops watching children, clear false positive PARENT_WATCHED flags lazily in __fsnotify_parent() for each accessed child.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Avoid race between dcn10_set_drr() and dc_state_destruct() dc_state_destruct() nulls the resource context of the DC state. The pipe context passed to dcn10_set_drr() is a member of this resource context. If dc_state_destruct() is called parallel to the IRQ processing (which calls dcn10_set_drr() at some point), we can end up using already nulled function callback fields of struct stream_resource. The logic in dcn10_set_drr() already tries to avoid this, by checking tg against NULL. But if the nulling happens exactly after the NULL check and before the next access, then we get a race. Avoid this by copying tg first to a local variable, and then use this variable for all the operations. This should work, as long as nobody frees the resource pool where the timing generators live. (cherry picked from commit a3cc326a43bdc48fbdf53443e1027a03e309b643)

Race condition in the tty_fasync function in drivers/char/tty_io.c in the Linux kernel before 2.6.32.6 allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via unknown vectors, related to the put_tty_queue and __f_setown functions. NOTE: the vulnerability was addressed in a different way in 2.6.32.9.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Avoid race between dcn35_set_drr() and dc_state_destruct() dc_state_destruct() nulls the resource context of the DC state. The pipe context passed to dcn35_set_drr() is a member of this resource context. If dc_state_destruct() is called parallel to the IRQ processing (which calls dcn35_set_drr() at some point), we can end up using already nulled function callback fields of struct stream_resource. The logic in dcn35_set_drr() already tries to avoid this, by checking tg against NULL. But if the nulling happens exactly after the NULL check and before the next access, then we get a race. Avoid this by copying tg first to a local variable, and then use this variable for all the operations. This should work, as long as nobody frees the resource pool where the timing generators live. (cherry picked from commit 0607a50c004798a96e62c089a4c34c220179dcb5)

In the Linux kernel, the following vulnerability has been resolved: net/mlx5: Always drain health in shutdown callback There is no point in recovery during device shutdown. if health work started need to wait for it to avoid races and NULL pointer access. Hence, drain health WQ on shutdown callback.

In the Linux kernel, the following vulnerability has been resolved: ice: Don't process extts if PTP is disabled The ice_ptp_extts_event() function can race with ice_ptp_release() and result in a NULL pointer dereference which leads to a kernel panic. Panic occurs because the ice_ptp_extts_event() function calls ptp_clock_event() with a NULL pointer. The ice driver has already released the PTP clock by the time the interrupt for the next external timestamp event occurs. To fix this, modify the ice_ptp_extts_event() function to check the PTP state and bail early if PTP is not ready.

In the Linux kernel, the following vulnerability has been resolved: mm/sparsemem: fix race in accessing memory_section->usage The below race is observed on a PFN which falls into the device memory region with the system memory configuration where PFN's are such that [ZONE_NORMAL ZONE_DEVICE ZONE_NORMAL]. Since normal zone start and end pfn contains the device memory PFN's as well, the compaction triggered will try on the device memory PFN's too though they end up in NOP(because pfn_to_online_page() returns NULL for ZONE_DEVICE memory sections). When from other core, the section mappings are being removed for the ZONE_DEVICE region, that the PFN in question belongs to, on which compaction is currently being operated is resulting into the kernel crash with CONFIG_SPASEMEM_VMEMAP enabled. The crash logs can be seen at [1]. compact_zone() memunmap_pages ------------- --------------- __pageblock_pfn_to_page ...... (a)pfn_valid(): valid_section()//return true (b)__remove_pages()-> sparse_remove_section()-> section_deactivate(): [Free the array ms->usage and set ms->usage = NULL] pfn_section_valid() [Access ms->usage which is NULL] NOTE: From the above it can be said that the race is reduced to between the pfn_valid()/pfn_section_valid() and the section deactivate with SPASEMEM_VMEMAP enabled. The commit b943f045a9af("mm/sparse: fix kernel crash with pfn_section_valid check") tried to address the same problem by clearing the SECTION_HAS_MEM_MAP with the expectation of valid_section() returns false thus ms->usage is not accessed. Fix this issue by the below steps: a) Clear SECTION_HAS_MEM_MAP before freeing the ->usage. b) RCU protected read side critical section will either return NULL when SECTION_HAS_MEM_MAP is cleared or can successfully access ->usage. c) Free the ->usage with kfree_rcu() and set ms->usage = NULL. No attempt will be made to access ->usage after this as the SECTION_HAS_MEM_MAP is cleared thus valid_section() return false. Thanks to David/Pavan for their inputs on this patch. [1] https://lore.kernel.org/linux-mm/994410bb-89aa-d987-1f50-f514903c55aa@quicinc.com/ On Snapdragon SoC, with the mentioned memory configuration of PFN's as [ZONE_NORMAL ZONE_DEVICE ZONE_NORMAL], we are able to see bunch of issues daily while testing on a device farm. For this particular issue below is the log. Though the below log is not directly pointing to the pfn_section_valid(){ ms->usage;}, when we loaded this dump on T32 lauterbach tool, it is pointing. [ 540.578056] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 540.578068] Mem abort info: [ 540.578070] ESR = 0x0000000096000005 [ 540.578073] EC = 0x25: DABT (current EL), IL = 32 bits [ 540.578077] SET = 0, FnV = 0 [ 540.578080] EA = 0, S1PTW = 0 [ 540.578082] FSC = 0x05: level 1 translation fault [ 540.578085] Data abort info: [ 540.578086] ISV = 0, ISS = 0x00000005 [ 540.578088] CM = 0, WnR = 0 [ 540.579431] pstate: 82400005 (Nzcv daif +PAN -UAO +TCO -DIT -SSBSBTYPE=--) [ 540.579436] pc : __pageblock_pfn_to_page+0x6c/0x14c [ 540.579454] lr : compact_zone+0x994/0x1058 [ 540.579460] sp : ffffffc03579b510 [ 540.579463] x29: ffffffc03579b510 x28: 0000000000235800 x27:000000000000000c [ 540.579470] x26: 0000000000235c00 x25: 0000000000000068 x24:ffffffc03579b640 [ 540.579477] x23: 0000000000000001 x22: ffffffc03579b660 x21:0000000000000000 [ 540.579483] x20: 0000000000235bff x19: ffffffdebf7e3940 x18:ffffffdebf66d140 [ 540.579489] x17: 00000000739ba063 x16: 00000000739ba063 x15:00000000009f4bff [ 540.579495] x14: 0000008000000000 x13: 0000000000000000 x12:0000000000000001 [ 540.579501] x11: 0000000000000000 x10: 0000000000000000 x9 :ffffff897d2cd440 [ 540.579507] x8 : 0000000000000000 x7 : 0000000000000000 x6 :ffffffc03579b5b4 [ 540.579512] x5 : 0000000000027f25 x4 : ffffffc03579b5b8 x3 :0000000000000 ---truncated---

In the Linux kernel, the following vulnerability has been resolved: pds_core: Prevent race issues involving the adminq There are multiple paths that can result in using the pdsc's adminq. [1] pdsc_adminq_isr and the resulting work from queue_work(), i.e. pdsc_work_thread()->pdsc_process_adminq() [2] pdsc_adminq_post() When the device goes through reset via PCIe reset and/or a fw_down/fw_up cycle due to bad PCIe state or bad device state the adminq is destroyed and recreated. A NULL pointer dereference can happen if [1] or [2] happens after the adminq is already destroyed. In order to fix this, add some further state checks and implement reference counting for adminq uses. Reference counting was used because multiple threads can attempt to access the adminq at the same time via [1] or [2]. Additionally, multiple clients (i.e. pds-vfio-pci) can be using [2] at the same time. The adminq_refcnt is initialized to 1 when the adminq has been allocated and is ready to use. Users/clients of the adminq (i.e. [1] and [2]) will increment the refcnt when they are using the adminq. When the driver goes into a fw_down cycle it will set the PDSC_S_FW_DEAD bit and then wait for the adminq_refcnt to hit 1. Setting the PDSC_S_FW_DEAD before waiting will prevent any further adminq_refcnt increments. Waiting for the adminq_refcnt to hit 1 allows for any current users of the adminq to finish before the driver frees the adminq. Once the adminq_refcnt hits 1 the driver clears the refcnt to signify that the adminq is deleted and cannot be used. On the fw_up cycle the driver will once again initialize the adminq_refcnt to 1 allowing the adminq to be used again.

In the Linux kernel, the following vulnerability has been resolved: hv_netvsc: Fix race condition between netvsc_probe and netvsc_remove In commit ac5047671758 ("hv_netvsc: Disable NAPI before closing the VMBus channel"), napi_disable was getting called for all channels, including all subchannels without confirming if they are enabled or not. This caused hv_netvsc getting hung at napi_disable, when netvsc_probe() has finished running but nvdev->subchan_work has not started yet. netvsc_subchan_work() -> rndis_set_subchannel() has not created the sub-channels and because of that netvsc_sc_open() is not running. netvsc_remove() calls cancel_work_sync(&nvdev->subchan_work), for which netvsc_subchan_work did not run. netif_napi_add() sets the bit NAPI_STATE_SCHED because it ensures NAPI cannot be scheduled. Then netvsc_sc_open() -> napi_enable will clear the NAPIF_STATE_SCHED bit, so it can be scheduled. napi_disable() does the opposite. Now during netvsc_device_remove(), when napi_disable is called for those subchannels, napi_disable gets stuck on infinite msleep. This fix addresses this problem by ensuring that napi_disable() is not getting called for non-enabled NAPI struct. But netif_napi_del() is still necessary for these non-enabled NAPI struct for cleanup purpose. Call trace: [ 654.559417] task:modprobe state:D stack: 0 pid: 2321 ppid: 1091 flags:0x00004002 [ 654.568030] Call Trace: [ 654.571221] <TASK> [ 654.573790] __schedule+0x2d6/0x960 [ 654.577733] schedule+0x69/0xf0 [ 654.581214] schedule_timeout+0x87/0x140 [ 654.585463] ? __bpf_trace_tick_stop+0x20/0x20 [ 654.590291] msleep+0x2d/0x40 [ 654.593625] napi_disable+0x2b/0x80 [ 654.597437] netvsc_device_remove+0x8a/0x1f0 [hv_netvsc] [ 654.603935] rndis_filter_device_remove+0x194/0x1c0 [hv_netvsc] [ 654.611101] ? do_wait_intr+0xb0/0xb0 [ 654.615753] netvsc_remove+0x7c/0x120 [hv_netvsc] [ 654.621675] vmbus_remove+0x27/0x40 [hv_vmbus]

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to truncate meta inode pages forcely Below race case can cause data corruption: Thread A GC thread - gc_data_segment - ra_data_block - locked meta_inode page - f2fs_inplace_write_data - invalidate_mapping_pages : fail to invalidate meta_inode page due to lock failure or dirty|writeback status - f2fs_submit_page_bio : write last dirty data to old blkaddr - move_data_block - load old data from meta_inode page - f2fs_submit_page_write : write old data to new blkaddr Because invalidate_mapping_pages() will skip invalidating page which has unclear status including locked, dirty, writeback and so on, so we need to use truncate_inode_pages_range() instead of invalidate_mapping_pages() to make sure meta_inode page will be dropped.

In the Linux kernel, the following vulnerability has been resolved: tls: fix race between async notify and socket close The submitting thread (one which called recvmsg/sendmsg) may exit as soon as the async crypto handler calls complete() so any code past that point risks touching already freed data. Try to avoid the locking and extra flags altogether. Have the main thread hold an extra reference, this way we can depend solely on the atomic ref counter for synchronization. Don't futz with reiniting the completion, either, we are now tightly controlling when completion fires.

In the Linux kernel, the following vulnerability has been resolved: wireguard: receive: annotate data-race around receiving_counter.counter Syzkaller with KCSAN identified a data-race issue when accessing keypair->receiving_counter.counter. Use READ_ONCE() and WRITE_ONCE() annotations to mark the data race as intentional. BUG: KCSAN: data-race in wg_packet_decrypt_worker / wg_packet_rx_poll write to 0xffff888107765888 of 8 bytes by interrupt on cpu 0: counter_validate drivers/net/wireguard/receive.c:321 [inline] wg_packet_rx_poll+0x3ac/0xf00 drivers/net/wireguard/receive.c:461 __napi_poll+0x60/0x3b0 net/core/dev.c:6536 napi_poll net/core/dev.c:6605 [inline] net_rx_action+0x32b/0x750 net/core/dev.c:6738 __do_softirq+0xc4/0x279 kernel/softirq.c:553 do_softirq+0x5e/0x90 kernel/softirq.c:454 __local_bh_enable_ip+0x64/0x70 kernel/softirq.c:381 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:167 [inline] _raw_spin_unlock_bh+0x36/0x40 kernel/locking/spinlock.c:210 spin_unlock_bh include/linux/spinlock.h:396 [inline] ptr_ring_consume_bh include/linux/ptr_ring.h:367 [inline] wg_packet_decrypt_worker+0x6c5/0x700 drivers/net/wireguard/receive.c:499 process_one_work kernel/workqueue.c:2633 [inline] ... read to 0xffff888107765888 of 8 bytes by task 3196 on cpu 1: decrypt_packet drivers/net/wireguard/receive.c:252 [inline] wg_packet_decrypt_worker+0x220/0x700 drivers/net/wireguard/receive.c:501 process_one_work kernel/workqueue.c:2633 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2706 worker_thread+0x525/0x730 kernel/workqueue.c:2787 ...

In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: fix performance regression in swap operation The patch "netfilter: ipset: fix race condition between swap/destroy and kernel side add/del/test", commit 28628fa9 fixes a race condition. But the synchronize_rcu() added to the swap function unnecessarily slows it down: it can safely be moved to destroy and use call_rcu() instead. Eric Dumazet pointed out that simply calling the destroy functions as rcu callback does not work: sets with timeout use garbage collectors which need cancelling at destroy which can wait. Therefore the destroy functions are split into two: cancelling garbage collectors safely at executing the command received by netlink and moving the remaining part only into the rcu callback.

In the Linux kernel, the following vulnerability has been resolved: quota: Fix potential NULL pointer dereference Below race may cause NULL pointer dereference P1 P2 dquot_free_inode quota_off drop_dquot_ref remove_dquot_ref dquots = i_dquot(inode) dquots = i_dquot(inode) srcu_read_lock dquots[cnt]) != NULL (1) dquots[type] = NULL (2) spin_lock(&dquots[cnt]->dq_dqb_lock) (3) .... If dquot_free_inode(or other routines) checks inode's quota pointers (1) before quota_off sets it to NULL(2) and use it (3) after that, NULL pointer dereference will be triggered. So let's fix it by using a temporary pointer to avoid this issue.

Race condition in the ext4_file_write_iter function in fs/ext4/file.c in the Linux kernel through 3.17 allows local users to cause a denial of service (file unavailability) via a combination of a write action and an F_SETFL fcntl operation for the O_DIRECT flag.

In the Linux kernel, the following vulnerability has been resolved: blk-mq: fix IO hang from sbitmap wakeup race In blk_mq_mark_tag_wait(), __add_wait_queue() may be re-ordered with the following blk_mq_get_driver_tag() in case of getting driver tag failure. Then in __sbitmap_queue_wake_up(), waitqueue_active() may not observe the added waiter in blk_mq_mark_tag_wait() and wake up nothing, meantime blk_mq_mark_tag_wait() can't get driver tag successfully. This issue can be reproduced by running the following test in loop, and fio hang can be observed in < 30min when running it on my test VM in laptop. modprobe -r scsi_debug modprobe scsi_debug delay=0 dev_size_mb=4096 max_queue=1 host_max_queue=1 submit_queues=4 dev=`ls -d /sys/bus/pseudo/drivers/scsi_debug/adapter*/host*/target*/*/block/* | head -1 | xargs basename` fio --filename=/dev/"$dev" --direct=1 --rw=randrw --bs=4k --iodepth=1 \ --runtime=100 --numjobs=40 --time_based --name=test \ --ioengine=libaio Fix the issue by adding one explicit barrier in blk_mq_mark_tag_wait(), which is just fine in case of running out of tag.

A race condition was found in the Linux kernel's scsi device driver in lpfc_unregister_fcf_rescan() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

In the Linux kernel, the following vulnerability has been resolved: drm/bridge: sii902x: Fix probing race issue A null pointer dereference crash has been observed rarely on TI platforms using sii9022 bridge: [ 53.271356] sii902x_get_edid+0x34/0x70 [sii902x] [ 53.276066] sii902x_bridge_get_edid+0x14/0x20 [sii902x] [ 53.281381] drm_bridge_get_edid+0x20/0x34 [drm] [ 53.286305] drm_bridge_connector_get_modes+0x8c/0xcc [drm_kms_helper] [ 53.292955] drm_helper_probe_single_connector_modes+0x190/0x538 [drm_kms_helper] [ 53.300510] drm_client_modeset_probe+0x1f0/0xbd4 [drm] [ 53.305958] __drm_fb_helper_initial_config_and_unlock+0x50/0x510 [drm_kms_helper] [ 53.313611] drm_fb_helper_initial_config+0x48/0x58 [drm_kms_helper] [ 53.320039] drm_fbdev_dma_client_hotplug+0x84/0xd4 [drm_dma_helper] [ 53.326401] drm_client_register+0x5c/0xa0 [drm] [ 53.331216] drm_fbdev_dma_setup+0xc8/0x13c [drm_dma_helper] [ 53.336881] tidss_probe+0x128/0x264 [tidss] [ 53.341174] platform_probe+0x68/0xc4 [ 53.344841] really_probe+0x188/0x3c4 [ 53.348501] __driver_probe_device+0x7c/0x16c [ 53.352854] driver_probe_device+0x3c/0x10c [ 53.357033] __device_attach_driver+0xbc/0x158 [ 53.361472] bus_for_each_drv+0x88/0xe8 [ 53.365303] __device_attach+0xa0/0x1b4 [ 53.369135] device_initial_probe+0x14/0x20 [ 53.373314] bus_probe_device+0xb0/0xb4 [ 53.377145] deferred_probe_work_func+0xcc/0x124 [ 53.381757] process_one_work+0x1f0/0x518 [ 53.385770] worker_thread+0x1e8/0x3dc [ 53.389519] kthread+0x11c/0x120 [ 53.392750] ret_from_fork+0x10/0x20 The issue here is as follows: - tidss probes, but is deferred as sii902x is still missing. - sii902x starts probing and enters sii902x_init(). - sii902x calls drm_bridge_add(). Now the sii902x bridge is ready from DRM's perspective. - sii902x calls sii902x_audio_codec_init() and platform_device_register_data() - The registration of the audio platform device causes probing of the deferred devices. - tidss probes, which eventually causes sii902x_bridge_get_edid() to be called. - sii902x_bridge_get_edid() tries to use the i2c to read the edid. However, the sii902x driver has not set up the i2c part yet, leading to the crash. Fix this by moving the drm_bridge_add() to the end of the sii902x_init(), which is also at the very end of sii902x_probe().

A race condition was found in the Linux kernel's media/dvb-core in dvbdmx_write() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

A race condition was found in the Linux kernel's drm/exynos device driver in exynos_drm_crtc_atomic_disable() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

A race condition was found in the Linux kernel's sound/hda device driver in snd_hdac_regmap_sync() function. This can result in a null pointer dereference issue, possibly leading to a kernel panic or denial of service issue.

In the Linux kernel, the following vulnerability has been resolved: drm/amd/display: Disable DMCUB timeout for DCN35 [Why] DMCUB can intermittently take longer than expected to process commands. Old ASIC policy was to continue while logging a diagnostic error - which works fine for ASIC without IPS, but with IPS this could lead to a race condition where we attempt to access DCN state while it's inaccessible, leading to a system hang when the NIU port is not disabled or register accesses that timeout and the display configuration in an undefined state. [How] We need to investigate why these accesses take longer than expected, but for now we should disable the timeout on DCN35 to avoid this race condition. Since the waits happen only at lower interrupt levels the risk of taking too long at higher IRQ and causing a system watchdog timeout are minimal.

In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix a race between socket set up and I/O thread creation In rxrpc_open_socket(), it sets up the socket and then sets up the I/O thread that will handle it. This is a problem, however, as there's a gap between the two phases in which a packet may come into rxrpc_encap_rcv() from the UDP packet but we oops when trying to wake the not-yet created I/O thread. As a quick fix, just make rxrpc_encap_rcv() discard the packet if there's no I/O thread yet. A better, but more intrusive fix would perhaps be to rearrange things such that the socket creation is done by the I/O thread.

In the Linux kernel, the following vulnerability has been resolved: scsi: lpfc: Ensure DA_ID handling completion before deleting an NPIV instance Deleting an NPIV instance requires all fabric ndlps to be released before an NPIV's resources can be torn down. Failure to release fabric ndlps beforehand opens kref imbalance race conditions. Fix by forcing the DA_ID to complete synchronously with usage of wait_queue.

In the Linux kernel, the following vulnerability has been resolved: nvme-pci: fix race condition between reset and nvme_dev_disable() nvme_dev_disable() modifies the dev->online_queues field, therefore nvme_pci_update_nr_queues() should avoid racing against it, otherwise we could end up passing invalid values to blk_mq_update_nr_hw_queues(). WARNING: CPU: 39 PID: 61303 at drivers/pci/msi/api.c:347 pci_irq_get_affinity+0x187/0x210 Workqueue: nvme-reset-wq nvme_reset_work [nvme] RIP: 0010:pci_irq_get_affinity+0x187/0x210 Call Trace: <TASK> ? blk_mq_pci_map_queues+0x87/0x3c0 ? pci_irq_get_affinity+0x187/0x210 blk_mq_pci_map_queues+0x87/0x3c0 nvme_pci_map_queues+0x189/0x460 [nvme] blk_mq_update_nr_hw_queues+0x2a/0x40 nvme_reset_work+0x1be/0x2a0 [nvme] Fix the bug by locking the shutdown_lock mutex before using dev->online_queues. Give up if nvme_dev_disable() is running or if it has been executed already.

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix to check atomic_file in f2fs ioctl interfaces Some f2fs ioctl interfaces like f2fs_ioc_set_pin_file(), f2fs_move_file_range(), and f2fs_defragment_range() missed to check atomic_write status, which may cause potential race issue, fix it.

In the Linux kernel, the following vulnerability has been resolved: ipv6: fix possible race in __fib6_drop_pcpu_from() syzbot found a race in __fib6_drop_pcpu_from() [1] If compiler reads more than once (*ppcpu_rt), second read could read NULL, if another cpu clears the value in rt6_get_pcpu_route(). Add a READ_ONCE() to prevent this race. Also add rcu_read_lock()/rcu_read_unlock() because we rely on RCU protection while dereferencing pcpu_rt. [1] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000012: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000090-0x0000000000000097] CPU: 0 PID: 7543 Comm: kworker/u8:17 Not tainted 6.10.0-rc1-syzkaller-00013-g2bfcfd584ff5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: netns cleanup_net RIP: 0010:__fib6_drop_pcpu_from.part.0+0x10a/0x370 net/ipv6/ip6_fib.c:984 Code: f8 48 c1 e8 03 80 3c 28 00 0f 85 16 02 00 00 4d 8b 3f 4d 85 ff 74 31 e8 74 a7 fa f7 49 8d bf 90 00 00 00 48 89 f8 48 c1 e8 03 <80> 3c 28 00 0f 85 1e 02 00 00 49 8b 87 90 00 00 00 48 8b 0c 24 48 RSP: 0018:ffffc900040df070 EFLAGS: 00010206 RAX: 0000000000000012 RBX: 0000000000000001 RCX: ffffffff89932e16 RDX: ffff888049dd1e00 RSI: ffffffff89932d7c RDI: 0000000000000091 RBP: dffffc0000000000 R08: 0000000000000005 R09: 0000000000000007 R10: 0000000000000001 R11: 0000000000000006 R12: ffff88807fa080b8 R13: fffffbfff1a9a07d R14: ffffed100ff41022 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32c26000 CR3: 000000005d56e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> __fib6_drop_pcpu_from net/ipv6/ip6_fib.c:966 [inline] fib6_drop_pcpu_from net/ipv6/ip6_fib.c:1027 [inline] fib6_purge_rt+0x7f2/0x9f0 net/ipv6/ip6_fib.c:1038 fib6_del_route net/ipv6/ip6_fib.c:1998 [inline] fib6_del+0xa70/0x17b0 net/ipv6/ip6_fib.c:2043 fib6_clean_node+0x426/0x5b0 net/ipv6/ip6_fib.c:2205 fib6_walk_continue+0x44f/0x8d0 net/ipv6/ip6_fib.c:2127 fib6_walk+0x182/0x370 net/ipv6/ip6_fib.c:2175 fib6_clean_tree+0xd7/0x120 net/ipv6/ip6_fib.c:2255 __fib6_clean_all+0x100/0x2d0 net/ipv6/ip6_fib.c:2271 rt6_sync_down_dev net/ipv6/route.c:4906 [inline] rt6_disable_ip+0x7ed/0xa00 net/ipv6/route.c:4911 addrconf_ifdown.isra.0+0x117/0x1b40 net/ipv6/addrconf.c:3855 addrconf_notify+0x223/0x19e0 net/ipv6/addrconf.c:3778 notifier_call_chain+0xb9/0x410 kernel/notifier.c:93 call_netdevice_notifiers_info+0xbe/0x140 net/core/dev.c:1992 call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] dev_close_many+0x333/0x6a0 net/core/dev.c:1585 unregister_netdevice_many_notify+0x46d/0x19f0 net/core/dev.c:11193 unregister_netdevice_many net/core/dev.c:11276 [inline] default_device_exit_batch+0x85b/0xae0 net/core/dev.c:11759 ops_exit_list+0x128/0x180 net/core/net_namespace.c:178 cleanup_net+0x5b7/0xbf0 net/core/net_namespace.c:640 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

In the Linux kernel, the following vulnerability has been resolved: tracing/timerlat: Fix a race during cpuhp processing There is another found exception that the "timerlat/1" thread was scheduled on CPU0, and lead to timer corruption finally: ``` ODEBUG: init active (active state 0) object: ffff888237c2e108 object type: hrtimer hint: timerlat_irq+0x0/0x220 WARNING: CPU: 0 PID: 426 at lib/debugobjects.c:518 debug_print_object+0x7d/0xb0 Modules linked in: CPU: 0 UID: 0 PID: 426 Comm: timerlat/1 Not tainted 6.11.0-rc7+ #45 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:debug_print_object+0x7d/0xb0 ... Call Trace: <TASK> ? __warn+0x7c/0x110 ? debug_print_object+0x7d/0xb0 ? report_bug+0xf1/0x1d0 ? prb_read_valid+0x17/0x20 ? handle_bug+0x3f/0x70 ? exc_invalid_op+0x13/0x60 ? asm_exc_invalid_op+0x16/0x20 ? debug_print_object+0x7d/0xb0 ? debug_print_object+0x7d/0xb0 ? __pfx_timerlat_irq+0x10/0x10 __debug_object_init+0x110/0x150 hrtimer_init+0x1d/0x60 timerlat_main+0xab/0x2d0 ? __pfx_timerlat_main+0x10/0x10 kthread+0xb7/0xe0 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x2d/0x40 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 </TASK> ``` After tracing the scheduling event, it was discovered that the migration of the "timerlat/1" thread was performed during thread creation. Further analysis confirmed that it is because the CPU online processing for osnoise is implemented through workers, which is asynchronous with the offline processing. When the worker was scheduled to create a thread, the CPU may has already been removed from the cpu_online_mask during the offline process, resulting in the inability to select the right CPU: T1 | T2 [CPUHP_ONLINE] | cpu_device_down() osnoise_hotplug_workfn() | | cpus_write_lock() | takedown_cpu(1) | cpus_write_unlock() [CPUHP_OFFLINE] | cpus_read_lock() | start_kthread(1) | cpus_read_unlock() | To fix this, skip online processing if the CPU is already offline.

In the Linux kernel, the following vulnerability has been resolved: sock_map: fix a NULL pointer dereference in sock_map_link_update_prog() The following race condition could trigger a NULL pointer dereference: sock_map_link_detach(): sock_map_link_update_prog(): mutex_lock(&sockmap_mutex); ... sockmap_link->map = NULL; mutex_unlock(&sockmap_mutex); mutex_lock(&sockmap_mutex); ... sock_map_prog_link_lookup(sockmap_link->map); mutex_unlock(&sockmap_mutex); <continue> Fix it by adding a NULL pointer check. In this specific case, it makes no sense to update a link which is being released.

In the Linux kernel, the following vulnerability has been resolved: net: dsa: improve shutdown sequence Alexander Sverdlin presents 2 problems during shutdown with the lan9303 driver. One is specific to lan9303 and the other just happens to reproduce there. The first problem is that lan9303 is unique among DSA drivers in that it calls dev_get_drvdata() at "arbitrary runtime" (not probe, not shutdown, not remove): phy_state_machine() -> ... -> dsa_user_phy_read() -> ds->ops->phy_read() -> lan9303_phy_read() -> chip->ops->phy_read() -> lan9303_mdio_phy_read() -> dev_get_drvdata() But we never stop the phy_state_machine(), so it may continue to run after dsa_switch_shutdown(). Our common pattern in all DSA drivers is to set drvdata to NULL to suppress the remove() method that may come afterwards. But in this case it will result in an NPD. The second problem is that the way in which we set dp->conduit->dsa_ptr = NULL; is concurrent with receive packet processing. dsa_switch_rcv() checks once whether dev->dsa_ptr is NULL, but afterwards, rather than continuing to use that non-NULL value, dev->dsa_ptr is dereferenced again and again without NULL checks: dsa_conduit_find_user() and many other places. In between dereferences, there is no locking to ensure that what was valid once continues to be valid. Both problems have the common aspect that closing the conduit interface solves them. In the first case, dev_close(conduit) triggers the NETDEV_GOING_DOWN event in dsa_user_netdevice_event() which closes user ports as well. dsa_port_disable_rt() calls phylink_stop(), which synchronously stops the phylink state machine, and ds->ops->phy_read() will thus no longer call into the driver after this point. In the second case, dev_close(conduit) should do this, as per Documentation/networking/driver.rst: | Quiescence | ---------- | | After the ndo_stop routine has been called, the hardware must | not receive or transmit any data. All in flight packets must | be aborted. If necessary, poll or wait for completion of | any reset commands. So it should be sufficient to ensure that later, when we zeroize conduit->dsa_ptr, there will be no concurrent dsa_switch_rcv() call on this conduit. The addition of the netif_device_detach() function is to ensure that ioctls, rtnetlinks and ethtool requests on the user ports no longer propagate down to the driver - we're no longer prepared to handle them. The race condition actually did not exist when commit 0650bf52b31f ("net: dsa: be compatible with masters which unregister on shutdown") first introduced dsa_switch_shutdown(). It was created later, when we stopped unregistering the user interfaces from a bad spot, and we just replaced that sequence with a racy zeroization of conduit->dsa_ptr (one which doesn't ensure that the interfaces aren't up).